The present invention generally relates to characterization methods for female pelvic tissues. Specifically, the invention describes methods and devices for characterizing pelvic floor support structures including vaginal tissue elasticity and muscle strength.
Various stages of pelvic organ abnormality including a pelvic organ prolapse (POP) are highly prevalent affecting at least 50% of women in the US during their lifetimes. Some loss of utero-vaginal support occurs in most adult women. POP is the leading indication for hysterectomy in postmenopausal women and accounts for 15-18% of procedures in all age-groups [Kesharvarz H, Hillis S D, Kieke B A, Marchbanks P A. Hysterectomy surveillance—United States 1994-1999. MMWR Surveill Summ 2002; 51 (5505):1-8]. Beyond the physical impact of POP, women with progressing pelvic organ abnormality score poorer on both generic and condition-specific quality-of-life scales [Jelovsek J E, Barber M D. Women seeking treatment for advanced pelvic organ abnormality have decreased body image and quality of life. Am J Obstet Gynecol. 2006; 194: 1455-61.]. In addition, about one third of sexually active women with POP report that their condition interferes with sexual function [Barber M D, Visco A G, Wyman, et al. Sexual function in women with urinary incontinence and pelvic organ abnormality. Obstet Gynecol. 2002; 99:281-9.].
Conservative treatment of pelvic floor abnormalities includes lifestyle interventions, physical therapies, pelvic floor muscle training, scheduled voiding regimens, electrical and magnetic stimulations, complementary and alternative medicines (i.e. those not considered part of the traditional biomedical model), anti-incontinence devices, supportive rings and pessaries, pads and catheters. Conservative therapies are usually low cost, and managed principally by the patient with instruction/supervision from a health professional. They differ from other forms of incontinence and prolapse management, in that they have a low risk of adverse effects and do not prejudice other subsequent treatments [Smith J H, Berghmans B, Burgio K, et al. Adult Conservative Managements. Committee 12. Incontinence. Eds: Abrams P, Cardozo L, Khoury S, Wein A. Health Publication Ltd.; 2009:1026-1120]. There is a need in quantitative characterization of outcome of the conservative treatment of pelvic floor abnormalities.
Women with symptomatic POP who fail or decline conservative management, including pessary use and physical therapy treatment, are candidates for reconstructive surgery. The overall goal for prolapse surgery is to give the most functional repair, while preventing recurrence of the condition and minimizing complications incurred by these repairs. Recurrence is one of the barriers in surgical correction most frustrating to both the surgeon and patient. Failure rates as high as 20-40% have been cited after surgical repair, with over 50% occurring within the first three years [Clemons J L, Myers D L, Aguilar V C, Arya L A. Vaginal paravaginal repair with an AlloDerm graft. Am J Obstet Gynecol. 2003; 189(6):1612-1618]. Since many patients with POP have inherently deficient or defective connective tissue, to minimize recurrence of POP many reconstructive surgeons have turned to the use of adjuvant materials for vaginal support. Such materials may include synthetic, allogenic, xenogenic or autologous grafts [Bako A, Dhar R. Review of synthetic mesh-related complications in pelvic floor reconstructive surgery. Int Urogynecol J Pelvic Floor Dysfunct. 2009; 20(1):103-111]. There is a need in quantitative characterization of outcome of pelvic floor reconstructive surgery.
Clinical diagnosis of vaginal abnormalities and ultimately POP involves taking a medical history and performing a manual physical examination when a physician inspects the urogenital areas and rectum for masses and indication of reduced muscle tone. The physician instructs the patient to cough, bear down or perform a Valsalva maneuver (a forceful attempt at exhalation with the mouth and nose closed) to see if and how far the vagina descends as the result of the additional abdominal pressure [Shagam J Y. Pelvic organ prolapse. Radiol Technol. 2006; 77(5):389-400].
While physical examination helps the clinician describe the extent of pelvic floor prolapse, it does not help in discerning the initial stage of abnormality development from the normal condition. Digital palpation does not provide quantitative tissue characterization to compare with normal elasticity of vaginal walls. It has poor sensitivity and is highly subjective.
Changes in the elasticity of the vaginal walls, connective support tissues, and muscles are significant factors in the development of POP. The high incidence of POP dictates the need for new effective methods of objective vaginal tissue characterization and early disease detection.